package org.codesandtags.projecteuler;




/**
 * Solucion del problema 11 de Project Euler
 * 
 * What is the greatest product of four adjacent numbers in any direction (up,
 * down, left, right, or diagonally) in the 2020 grid?
 * 
 * @author codesandtags
 * 
 */
public class Problem11 {

	public static void main(String[] args) {
	//Datos de entrada
	int[][] grid = 
			{{8, 02, 22, 97, 38, 15, 00, 40, 00, 75, 04, 05, 07, 78, 52, 12, 50, 77, 91,  8},
			{49, 49, 99, 40, 17, 81, 18, 57, 60, 87, 17, 40, 98, 43, 69, 48, 04, 56, 62, 00},
			{81, 49, 31, 73, 55, 79, 14, 29, 93, 71, 40, 67, 53, 88, 30, 03, 49, 13, 36, 65},
			{52, 70, 95, 23, 04, 60, 11, 42, 69, 24, 68, 56, 01, 32, 56, 71, 37, 02, 36, 91},
			{22, 31, 16, 71, 51, 67, 63, 89, 41, 92, 36, 54, 22, 40, 40, 28, 66, 33, 13, 80},
			{24, 47, 32, 60, 99, 03, 45, 02, 44, 75, 33, 53, 78, 36, 84, 20, 35, 17, 12, 50},
			{32, 98, 81, 28, 64, 23, 67, 10, 26, 38, 40, 67, 59, 54, 70, 66, 18, 38, 64, 70},
			{67, 26, 20, 68, 02, 62, 12, 20, 95, 63, 94, 39, 63,  8, 40, 91, 66, 49, 94, 21},
			{24, 55, 58, 05, 66, 73, 99, 26, 97, 17, 78, 78, 96, 83, 14, 88, 34, 89, 63, 72},
			{21, 36, 23,  9, 75, 00, 76, 44, 20, 45, 35, 14, 00, 61, 33, 97, 34, 31, 33, 95},
			{78, 17, 53, 28, 22, 75, 31, 67, 15, 94, 03, 80, 04, 62, 16, 14,  9, 53, 56, 92},
			{16, 39, 05, 42, 96, 35, 31, 47, 55, 58, 88, 24, 00, 17, 54, 24, 36, 29, 85, 57},
			{86, 56, 00, 48, 35, 71, 89, 07, 05, 44, 44, 37, 44, 60, 21, 58, 51, 54, 17, 58},
			{19, 80, 81, 68, 05, 94, 47, 69, 28, 73, 92, 13, 86, 52, 17, 77, 04, 89, 55, 40},
			{04, 52,  8, 83, 97, 35, 99, 16, 07, 97, 57, 32, 16, 26, 26, 79, 33, 27, 98, 66},
			{88, 36, 68, 87, 57, 62, 20, 72, 03, 46, 33, 67, 46, 55, 12, 32, 63, 93, 53, 69},
			{04, 42, 16, 73, 38, 25, 39, 11, 24, 94, 72, 18,  8, 46, 29, 32, 40, 62, 76, 36},
			{20, 69, 36, 41, 72, 30, 23, 88, 34, 62, 99, 69, 82, 67, 59, 85, 74, 04, 36, 16},
			{20, 73, 35, 29, 78, 31, 90, 01, 74, 31, 49, 71, 48, 86, 81, 16, 23, 57, 05, 54},
			{01, 70, 54, 71, 83, 51, 54, 69, 16, 92, 33, 48, 61, 43, 52, 01, 89, 19, 67, 48}};
				

		// Solucion
		Problem11 solve = new Problem11();
		System.out
				.println("The greatest Product of grid for 4 consecutives is : "
						+ solve.getGreatestProduct(grid, 4));
	}

	/**
	 * Obtiene y devuelve el mayor producto hallado en un consecutivo de digitos
	 * definidos en la firma del metodo, teniendo los datos de un arreglo
	 * bidimensional de numeros
	 * 
	 * @param grid
	 * @param consecutive
	 * @return
	 */
	public long getGreatestProduct(int grid[][], int consecutive) {
		long greatestProduct = 0l;

		// Recorrido horizontal
		for (int i = 0; i < grid.length; i++) {
			for (int j = 0; j <= grid[0].length - consecutive; j++) {
				long tempProduct = 1;
				for (int k = j; k < j + consecutive; k++) {
					tempProduct *= grid[i][k];
				}
				if (tempProduct > greatestProduct)
					greatestProduct = tempProduct;
			}
		}

		// Recorrido vertical
		for (int i = 0; i < grid.length; i++) {
			for (int j = 0; j <= grid[0].length - consecutive; j++) {
				long tempProduct = 1;
				for (int k = j; k < j + consecutive; k++) {
					tempProduct *= grid[k][i];
				}
				if (tempProduct > greatestProduct)
					greatestProduct = tempProduct;
			}
		}

		// Diagonal izquierda - derecha : Principal
		for (int i = 0; i <= grid.length - consecutive; i++) {
			for (int j = 0; j <= grid[0].length - consecutive; j++) {
				long tempProduct = 1;
				for (int k = j, x = 0; k < j + consecutive; k++, x++) {
					tempProduct *= grid[i + x][k];
				}
				if (tempProduct > greatestProduct)
					greatestProduct = tempProduct;
			}
		}

		// Diagonal derecha - izquierda : Inversa
		for (int i = 0; i <= grid.length - consecutive; i++) {
			for (int j = grid[0].length - consecutive - 1; j > 0; j--) {
				long tempProduct = 1;
				for (int k = j + consecutive, x = 0; k > j; k--, x++) {
					tempProduct *= grid[i + x][k];
				}
				if (tempProduct > greatestProduct)
					greatestProduct = tempProduct;
			}
		}
		// Hakuna Matata
		return greatestProduct;
	}
}
